title: Sequence-independent and rapid long-range charge transfer through DNA.
abstract: Interest in using DNA as a building block for nanoelectronic sensors and devices stems from its efficient hole-conducting properties and the relative ease with which it can be organized into predictable nanometre-sized two- and three-dimensional structures. However, because a hole migrates along DNA through the highest occupied molecular orbital of the guanine bases, its conductivity decreases as the adenine-thymine base-pair content increases. This means that there are limitations on what sequences can be used to construct functional nanoelectronic circuits, particularly those rich in adenine-thymine pairs. Here we show that the charge-transfer efficiency can be dramatically increased in a manner independent of guanine-cytosine content by adjusting the highest occupied molecular orbital level of the adenine-thymine base pair to be closer to that of the guanine-cytosine pair. This is achieved by substituting the N7 nitrogen atom of adenine with a C-H group to give 7-deazaadenine, which does not disturb the complementary base pairing observed in DNA.
authors.affiliation: The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan. kiyohiko@sanken.osaka-u.ac.jp
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Kawai
authors.forename: Haruka
authors.initials: H
authors.lastname: Kodera
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Osakada
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Majima
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry; D020029:Base Pairing; D001483:Base Sequence; D003596:Cytosine / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D006147:Guanine / Q000737:chemistry; D036103:Nanotechnology; D011789:Quantum Theory; D013941:Thymine / Q000737:chemistry
chemical_list: C043837:7-deazaadenine; D006147:Guanine; D003596:Cytosine; D004247:DNA; D000225:Adenine; D013941:Thymine